1. Field of the Invention
This invention relates to test fittings for pressure testing on waste or vent pipes and stacks.
2. Prior Art
In the installation of plumbing systems, particularly waste or vent pipes in buildings, it is necessary to pressure test the pipes for leaks. Prior art testing procedures have usually involved the incorporation of a short test section in the stack which is closed to the passage of fluid therethrough and which, after testing, must be removed and replaced with a comparable length of pipe.
One of the major problems of the prior art testing methods, particularly in multi-story buildings, resides in the disposal of the testing fluid above the test section and its replacement with a permanent stack section. It has usually been the practice to use an open fitting below the test section, into which the testing fluid from the stack above the test section can be discharged. However, in many instances, such fittings are not always easily available and disposal facilities, due to one cause or another, have sometimes failed, leading to excessive water damage.
In recent years a new method of pipe installation has been developed utilizing a type of coupling for adjoining cast iron pipe and pipe fittings which employs a compressible sealing gasket which can be wrapped about a pipe joint and compressed into fluid-tight sealing engagement with the pipe sections by a removable clamp. In this type of connection, the adjoining ends of the pipe sections to be coupled are spaced slightly apart to accept an annular sealing ridge on an inner face of the sealing gasket. It is with this type of cast iron pipe construction that the test fitting of the present invention is adapted to be used.